Battery Separator Slurry for Blocking Resistance and Electrolyte Wetting
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional secondary battery functional layers exhibit inadequate blocking resistance, electrolyte solution injectability, and high-temperature cycle characteristics, necessitating improvements for better performance.
Innovation Solution
A slurry composition for non-aqueous secondary battery functional layers incorporating a particulate polymer with a glass-transition temperature between 30°C and 95°C and a water-soluble polymer with a sulfo group-containing monomer unit at 3 mass% or more, optionally with a core-shell structure, enhances blocking resistance and electrolyte solution injectability, and improves high-temperature cycle characteristics.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a conventional functional layer composition is used, then the manufacturing process is simple, but the blocking resistance is insufficient
Solution Approach 1:
The patent applies composite materials by combining a water-soluble polymer containing sulfo group-containing monomer units with inorganic particles (such as alumina, silica, or boehmite) to form a functional layer. This composite structure provides both the binding functionality of the polymer and the heat resistance and mechanical strength of the inorganic particles, thereby achieving high blocking resistance while maintaining reasonable manufacturing complexity
Solution Approach 2:
The patent specifies precise parameter ranges for the water-soluble polymer, including the sulfo group content (0.1-10 mmol/g), molecular weight (10,000-1,000,000), and the ratio of water-soluble polymer to inorganic particles (1:99 to 50:50 by mass). These parameter optimizations enable the functional layer to achieve excellent blocking resistance and battery performance
2Reliability
If a conventional functional layer composition is used, then the composition is easy to prepare, but the electrolyte solution injectability is poor
Solution Approach 1:
The functional layer is formed as a porous structure by combining water-soluble polymer with inorganic particles, creating interconnected void spaces that facilitate electrolyte solution penetration. The porous morphology allows efficient electrolyte distribution throughout the battery while maintaining structural integrity
Solution Approach 2:
The water-soluble polymer acts as an intermediary between the inorganic particles and the electrolyte solution. It provides hydrophilic pathways that guide electrolyte penetration through the functional layer, enhancing injectability while the inorganic particles provide structural support
3Reliability
If a conventional functional layer composition is used, then the production cost is low, but the high-temperature cycle characteristics are insufficient
Solution Approach 1:
The patent optimizes the glass transition temperature of the water-soluble polymer to be between -50°C and 0°C, and controls the sulfo group content within specific ranges. These parameter optimizations ensure the functional layer maintains structural stability and binding effectiveness at high temperatures during battery cycling, improving high-temperature cycle characteristics
Solution Approach 2:
The combination of temperature-stable inorganic particles (alumina, silica, boehmite with high melting points) and the optimized water-soluble polymer creates a composite functional layer that resists thermal degradation during high-temperature cycling, enabling reliable battery operation under elevated temperature conditions
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The proposed slurry composition results in functional layers with improved blocking resistance, enhanced electrolyte solution injectability, and superior high-temperature cycle characteristics for non-aqueous secondary batteries.
Implementation Method 1
the water-soluble polymer includes a sulfo group-containing monomer unit in a proportion of 3.0 mass % or more
Implementation Method 2
the particulate polymer has at least one glass-transition temperature of not lower than 30° C. and not higher than 95° C.
Data Source
AI summary
A slurry composition for a non-aqueous secondary battery functional layer contains a particulate polymer having a glass-transition temperature within a specific range and a water-soluble polymer including a sulfo group-containing monomer unit in a proportion of 3 mass % or more.